Question

守则A运作良好。我在代码B中传递了一个类的参数，但是当我尝试使用EnableOrDisableCallMonitor（myContext，true，ReceiverSMS.class）调用函数时，代码B导致错误“它不适用于参数(Context, boolean, Class<ReceiverCall>)"，为什么？

此外，使用EnableOrDisableCallMonitor(myContext, true, Class<ReceiverSMS.class>)也会导致错误。

顺便说一句，代码C可以工作，但我不知道代码C是否是好方法。

  //----------------------------Code A-----------------------------------------
  public void EnableOrDisableCallMonitor(Context myContext, boolean isEnable) {
    ComponentName receiver = new ComponentName(myContext, ReceiverSMS.class);
    PackageManager pm = myContext.getPackageManager();

    int state = PackageManager.COMPONENT_ENABLED_STATE_DISABLED;
    if (isEnable) {
        state = PackageManager.COMPONENT_ENABLED_STATE_ENABLED;
    }
    pm.setComponentEnabledSetting(receiver, state,
            PackageManager.DONT_KILL_APP);
}



  //----------------------------Code B-----------------------------------------
  public void EnableOrDisableCallMonitor(Context myContext, boolean isEnable, Class<BroadcastReceiver> myClass) {
    ComponentName receiver = new ComponentName(myContext, myClass);
    PackageManager pm = myContext.getPackageManager();

    int state = PackageManager.COMPONENT_ENABLED_STATE_DISABLED;
    if (isEnable) {
        state = PackageManager.COMPONENT_ENABLED_STATE_ENABLED;
    }
    pm.setComponentEnabledSetting(receiver, state,
            PackageManager.DONT_KILL_APP);
}


 //----------------------------Code C-----------------------------------------

     public static void EnableOrDisableCallMonitor(Context myContext, boolean isEnable) {
       PublicParFun.EnableOrDisableBroadcastReceiver(myContext, isEnable,ReceiverCall.class);
     }         

     public static void EnableOrDisableBroadcastReceiver(Context myContext, boolean isEnable, Class myClass) {
        ComponentName receiver = new ComponentName(myContext, myClass);
        PackageManager pm = myContext.getPackageManager();

        int state = PackageManager.COMPONENT_ENABLED_STATE_DISABLED;
        if (isEnable) {
            state = PackageManager.COMPONENT_ENABLED_STATE_ENABLED;
        }
        pm.setComponentEnabledSetting(receiver, state,PackageManager.DONT_KILL_APP);
    }

Answer 1

您可以在param类型中使用泛型通配符。将Class<BroadcastReceiver> myClass更改为Class<? extends BroadcastReceiver> myClass。

Answer 2

更改第二种方法的签名（代码B中的签名），如下所示：

 public <T extends BroadcastReceiver> void EnableOrDisableCallMonitor(Context myContext, boolean isEnable, Class<T> myClass) {

如何传递类的参数？

2 个答案: